Methylene-bis-amines

In the alkaline medium, the reagent is postulated to be hydroxymethylamine or methylenc-bis-amine, - - although the participation of the N,0-acetal (Alkyl-O—CH2— N<), when the reaction is carried out in alcoholic solvents, cannot be excluded, and relevant amounts of methyleneimmonium cation are observed. The C-NMR measurements indicate that the methylolamine concentration is maximum when the molar ratio amine/aldehyde is ca. 1, whereas the formation of methylene-bis-amine is favored when this ratio increases. 

The reactants present in the equilibrium mixture, however, do not display the same reactivity indeed, studies carried out in an aprotic medium with acetylenic substrates and in an aqueous medium with polyacrylamide show that unlike methylolamine, methylene-bis-amine exhibits poor reactivity or none at all toward the above substrates. By contrast, methylene-bis-amine is an active intermediate in the aminomethylation of alkylphenols. ... 

When XH in 132 is an amino group identical to the NH residue, the symmetrically substituted cyclic methylene-bis-amines 133-135 (Fig. 47) are obtained. These products derive from substrates having cthylenediamine (133), propylenediaminc... 

Experimental evidence has lead to the conclusion that option a does not occur. Kinetic effects, pH dependencies, stoichiometry, and solvent polarity all led to the second option, b, as being the actual mechanistic pathway. Under basic conditions, the key reactive intermediate is the hydroxymethyl amine species 6. The Mannich base 5 is produced through a nucleophilic displacement by the corresponding anion (enolate) of the active hydrogen species 1. As the pH shifts to more acidic conditions, the relative proportions of the reactive intermediates also shift. The hydroxymethyl amine 6 becomes protonated and, with loss of an equivalent of water, generates iminium ion 7. Subsequently, this species can react directly with the active hydrogen species 1 or via the methylene bis-amine 8, formed by the addition of a second equivalent of amine 3 to iminium ion 7 (under conditions of excess amine). 

This reaction is reported to proceed at a rapid rate, with over 25% conversion in less than 0.001 s [3]. It can also proceed at very low temperatures, as in the middle of winter. Most primary substituted urea linkages, referred to as urea bonds, are more thermally stable than urethane bonds, by 20-30°C, but not in all cases. Polyamines based on aromatic amines are normally somewhat slower, especially if there are additional electron withdrawing moieties on the aromatic ring, such as chlorine or ester linkages [4]. Use of aliphatic isocyanates, such as methylene bis-4,4 -(cyclohexylisocyanate) (HnMDI), in place of MDI, has been shown to slow the gelation rate to about 60 s, with an amine chain extender present. Sterically hindered secondary amine-terminated polyols, in conjunction with certain aliphatic isocyanates, are reported to have slower gelation times, in some cases as long as 24 h [4]. 

Aromatic amine-terminated poly(tetrahydrofuran) — 650 MW Amine chain extender —4,4 -methylene bis(3-chloro-2,6,-diethyl aniline) Note the amine chain extender must be melted into the polyol at 160°C for 3 hrs under stirring, until completely melted. Once cooled, the chain extender remains liquid in the polyol. 

Chloroaniline(bis)methylene Methylene bis(chloroaniline) MBOCA Dichlorodiaminodiphenyl Methane under Aromatic Amines and Diamines ChloroaniUne, 4 under Aromatic Amines and Diamines... 

Aromatic amines, such as phenyl- -naphthylamine or condensation products of diphenylamine with acetone condensates, are excellent antioxidants and antiozonants but cause color development. From the sterically hindered phenols, monocyclic phenols, such as 2,6-di-teit-butyl-p-cresol, are less effective antioxidants but remain white and nontoxic during aging. They are, however, volatile and provide poor protection at elevated processing temperatures. Polycyclic phenols, such as 2,2 -methylene-bis (4-methyl-6-teit-butylphenol), are relatively nonvolatile, but become discolored by oxidation to a conjugated system. O Shea... 

These principles were used to assign Cls, Ols and Nls NEXAFS spectra of polymers important to the microelectronics industry. Interpretation of polyamic acid and polyimide spectra were aided by assigning the spectra of simpler polymers and monomers. The compounds studied in the form of spun films were poly(vinyl methyl ketone) (PVMK), poly(dimethyl phenylene oxide) (PMPO), poly(pyromellitimido 4,4-methylene bis-cyclohexyl amine) (PMDA-MBCA PI), and poly(pyromellitimido oxydianiline) (PMDA-ODA PI) and in the form of MBE-deposited films were poly(amic acid) (PAA), and PMDA-ODA PI. Changes in the NEXAFS spectra as a function of evaporated Cr overlayer thickness were measured for PVMK, PMPO and PMDA-ODA PI. Evolution of the NEXAFS spectra as a function of deposited organic film thickness and thermal treatment were measured for PAA on Cu and Cr substrates. 

PMPO represents the ODA part of PMDA-ODA PI and has four it resonances at 285.5, 287.2, 289.2 and 290.6 eV. These result from transitions from Cls core level states of two different energies (carbon bonded to C and H, and carbon bonded to C and O or C and N) to the two lowest it MO s for the arene ring it system. PVMK contains a carbonyl group and has an intense, sharp carbon NEXAFS peak at 286.7 eV attributable to a C = O it resonance, and a smaller peak at 288.7 eV from the C-H resonance. Poly(pyromellitimido 4,4 -methylene bis-cyclohexyl amine) (PMDA-MBCA PI) represents the PMDA part of PMDA-ODA PI without the added complication of any other it systems. As in the previously discussed case of propiolic acid, the arene and carbonyl it MO s on this polymer are in close enough proximity to interact and shift in energy. Thus, the arene it reso-... 

Methyleneimmonium salts 31 are conveniently prepared from mcihylene-bis-amines, formaldehyde-N,0-acetals, or methylene halogenides. Electrochemical reactions on various alkylamines have also been used to generate methyleneimmonium salts, and trimethylamine N-oxide 34 (Fig. 20) is reported as a source of the corresponding methyleneimmonium salt by reaction with trifluoroacetic anhydride. ... 

Amines, (see also Alkanolamines, Aminoacids, Aminoalcohols, Diamines, Melamine, Methylene-bi.s-amines), /2. 170, 200, 236... 

Both the above mechanisms are proposed in the literature with Mannich bases of nitroalkanes the substitution is clearly favored by the steric hindrance of the amine moiety, thus suggesting path 1, - whereas NMR studies on the reaction of P-amino-ketones with hydroxy coumarins do not reveal the presence of vinyl ketone intermediates. lodomethylated phenolic Mannich bases arc also claimed to react according to path 2, although the formation as by-products of dimers and methylene-bis-derivatives accounts for the participation of methylenequinone intermediates in the process. "... 

SYNS BIS AMINE CURALIN M CURENE 442 CYANASET DI(-4-AMINO-3-CHLOROPHENYL)METH-ANE DI-(4-AMINO-3-CLOROFENIL)METANO (ITALIAN) 4,4 -DIAMINO-3,3 -DICHLORODIPHENYL-METHANE 3,3 -DICHLOR-4,4 -DIAMINODIPHENYL-METHAN (GERMAN) 3,3 -DICHLORO-4,4 -DIAMINODIPHENYLMETHANE 3,3 -DICLORO-4,4 -DIAMINODIFENILMETANO (ITALIAN) MBOCA METHYLENE-4,4 -BIS(o-CHLOROANILINE) p,p -METHYLENEBIS(a-CHLOROANTLINE) p,p -METHYL-ENEBIS(o-CHLOROANILINE) 4,4 -METHYLENE(BIS)-CHLOROANILINE 4,4 -METHYLENEBIS(o-CHLORO-ANILINE) 4,4 -METHYLENEBIS-2-CHLOROBENZ-ENAMINE METHYLENE-BIS-ORTHOCHLOROANIL-... 

A series of polyamides were prepared by reaction of 4,4 -methylene bis(isocyanatobenzene), fffil, with various ketene aminals. A typical reaction using 1,1 bis(4-norpholino) ethylene, 13, and MDI to give polymer 14 is shewn. 

MONOMERS. Amine hardener, 4,4 -methylene-bis-(cyclohe.xylamine) (PACii ), was distilled under reduced pressure and stored under dry argon. It was melted under dry argon before use. Epoxy resin, diglycidyl ether of bisphencl A (DGEBA), had an epoxy equivalent weight of approximately 175 and was used without further purification. 

METHYLENE BIS(PHENYLISOCYANATE) or METHYLENE BISPHENYL ISOCYANATE (101-68-8) Combustible solid (flash point 385°F/196°C). Violent reaction with acids, bases, alcohols, amines. Incompatible with ammonia, amides, glycols, caprolactam. Unstable above 100°F/38°C. Attacks some plastics, rubber, and coatings. Reacts slowly with water. 

MBOCA is a synthetic chemical used in industry primarily to produce castable polyurethane parts. It also has a coating application in chemical reactions to "set" glues, plastics, and adhesives. Since plastics have many uses, MBOCA is used very widely. Other names for MBOCA include 4,4 -methylenebis(2-chloroaniline), bis amine, DACPM, MCA, methylenebis ortho chloroaniline, and MOCA. The name MBOCA comes from methylene bis ortho chloro aniline. Pure MBOCA is a colorless solid, but MBOCA is usually made and used as yellow, tan, or brown pellets. If MBOCA is heated above 205°C, it may decompose. MBOCA has no odor or taste. Chapter 3 contains more information on the chemical and physical properties of MBOCA. Chapter 4 contains more information on its production and use. 

Stoner GD, Shivapurkar NM, Schut HAJ, et al. 1988. DNA binding and adduct formation of 4,4 -methylene-bis(2-chloroaniline) (MOCA) in explant cultures of human and dog bladder. In King CM, Romano LJ, and Schultzle D, eds. Carcinogenic and mutagenic responses to aromatic amines and nitroarines. New York, NY Elsevier, 237-240. 

Sichuan Provincial Sanitary Station, "The Toxicology Research on Di-Ku-Shuang (N,N -methylene bis(1,3,4-thiadiazole-2-amine)" (August 1979, unpublished). 

The liquid polyurethane rubbers consist of polyurethanes with isocyanate end groups. They are generally cross-linked with weakly basic amines, for example, methylene bis(2-chloroaniline) ... 

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